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2003

14 April 2003, Human Genome Project announces that the analysis of human DNA is complete with 99% of the genome sequenced to a 99.99% accuracy

2003 — NASA's WMAP obtained full-sky detailed pictures of the cosmic microwave background radiation. The image can be interpreted to indicate that the universe is 13.7 billion years old (within one percent error) and confirm that the Lambda-CDM model and the inflationary theory are correct.
2003 — The Sloan Great Wall is discovered.

March 13 – The journal Nature reports that 350,000-year-old upright-walking human footprints have been found in Italy.

Astronomy
Mars retrograde motion during perigee 2003

February 11 – NASA's WMAP satellite completes the first detailed cosmic microwave background radiation map of the universe. The image reveals the universe is 13.7 billion years old (within one percent error) and provides evidence that supports the inflationary theory.
May 16 – Total lunar eclipse
May 31 – Annular solar eclipse in Northern Scotland, Faroe Islands, Greenland, and Iceland, with partial eclipse covering much of Europe and Russia.
August 25 – Opposition of Mars, closest approach to earth of Mars since 57,617 BC, at a distance of 55,758,006 kilometers.[1]
October–November – The sun is at solar maximum with a period of high activity, generating many large solar flares and coronal mass ejections.
November 9 – Total lunar eclipse.
November 14 – Trans-Neptunian object 90377 Sedna, one of the most distant objects in the Solar System, discovered by Palomar Observatory.[2]
November 23 – Total solar eclipse in Antarctica.
The 2dF Survey of galaxy redshifts is published.

Biology

October 13 – The open access scientific journal PLoS Biology from the Public Library of Science, commences operation.

Medicine

February 26 – A US businessman is diagnosed with the first known case of SARS in Hanoi, Vietnam, by WHO doctor Carlo Urbani.

February 1 – Space Shuttle Columbia disintegrates over Texas upon reentry killing all seven astronauts on board.
June 2 – The first European Mars mission Mars Express launched.
September 27 – The first European lunar mission Smart 1 launched.
October 15 – The People's Republic of China launches Shenzhou 5, their first manned space mission.
December 25 – Mars Express enters orbit around Mars. Its lander, Beagle 2 was to land on the surface but is lost (presumed crashed).

Technology

March – The world's first digital camera with an organic light-emitting diode (OLED) display is released by Kodak.
July 30 – The last old-style Volkswagen Beetle rolls off its production line in Puebla, Puebla, Mexico.
October 24 – Concorde makes its last flight, bringing the era of civilian supersonic travel to a close for the foreseeable future.
Intel releases the Pentium M microprocessor.

Births

May 4 – Idaho Gem, the world's first cloned mule.
May 28 – Prometea, the first cloned horse.